Print b-tree tuples

Hello,

I'm trying to print out the tuples in the b-tree nodes for analysis, but when iterate over more than the first entry of the tuples (scanKey++), I strangely get the error below on query execution:
ERROR:  relation "simpletest" does not exist
LINE 1: SELECT * FROM simpletest WHERE id = 50;

Any help with reviewing my my small attached patch would be greatly appreciated!

Regards,
Samuel Vogel